Material Considerations

DOE-HDBK-1132-99

The treatment portion of the off-gas system typically consists of air scrubbers

and HEPA filtration for particulate removal plus nitrous oxide reduction

through addition of ammonia in the presence of a catalyst.

Material Considerations. The chemical make-up of the off-gas stream requires

2.14.13

special attention. Typically, resistance to the corrosive characteristics of the off-

gas will dictate the types of materials used in the system. Material selections

typically include the 300 series of stainless steels, Inconel,TM and Hastalloy.TM

2.14.14

Process Development . Vitrification development is the process by which a

recipe and protocol are developed for the manufacture of an acceptable high-

level waste product. In particular, this activity focuses on developing and

refining the process for manufacturing the vitrified high-level waste into a

glass matrix exclusive of the canister. The development process focuses

primarily on two areas:

identification and development of the final waste glass product

composition and

development of the process for achieving the final waste glass product

given the available technology.

Development of the final waste glass product composition, frequently referred

to as the "arget composition,"is driven by a number of factors, including

regulatory performance specifications, behavior of the target composition in

the melter, and compatibility with the melter technology.

Regulatory requirements are issued through various DOE Offices including

the Office of Civilian Radioactive Waste Management (DOE-RW) and Office

of Environmental Management (DOE-EM). Those offices, respectively,

promulgate their requirements in the Waste Acceptance System

Requirements Document and Waste Acceptance Product Specifications for

Vitrified High-Level Waste Forms. Each of these documents contains the

technical specifications that the wastes produced must meet for acceptance of

their vitrified high-level waste into the repository. As such, among other

characteristics, target compositions exhibit the characteristics necessary for

meeting these technical specifications. With respect to the glass waste form,

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